When you get on x-ray at the doctor’s office, here’s what’s happening: A machine shoots x—ray radiation through your whole body, and a detector on the other side of you absorbs the radiation that makes it through. X-rays have just the right wavelength such that they easily pass through the soft parts of your body (like your organs) while they are absorbed by the harder parts of your body, like bones. So the detector can see your skeleton by looking at what’s missing from the resulting x-ray image.
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